Currently, opportunities for a search and sharing of various information in a radio communication environment such as with a portable computer, a mobile phone, and the like, have increased due to services provided by a communication network.
In this regard, a navigation system (hereinafter, referred to as ‘user terminal’) provides information helpful for the traveling of vehicles using an artificial satellite orbiting the Earth, and may be referred to as an automatic car navigation system.
The user terminal receives predetermined data from a Global Positioning System (GPS) satellite using a GPS receiver, and calculates a position of the user terminal based on the received data.
The user terminal of the vehicle may receive GPS signals from three satellites, from among a plurality of artificial satellites orbiting the Earth regardless of where the vehicle is traveling, and calculate the position of the user terminal based on the GPS signals received from the satellites.
The user terminal of the vehicle provides various traveling information based on position information acquired by calculating the position of the user terminal. The user terminal has been used for position calculation and navigation of a large-sized vehicle such as an aircraft, a ship, and the like, however, is currently widely used for a motor vehicle.
The user terminal provides various data such as current position information of a vehicle, traveling route information determined by a user, map information related with the position information and the traveling route information, traffic state information, and the like.
Also, the user terminal measures a current traveling speed of the vehicle, and displays traffic information (hereinafter, referred to as traveling state) according to the traveling speed, such as a delay state, congestion state, normal state, and the like.
An existing scheme for providing the traveling state according to the traveling speed measures a traveling speed for each link while traversing a path determined by a user, and compares the measured speed with a reference speed to thereby provide the traveling state.
For example, when it is assumed that the reference speed is 50 km/h, the traveling state may be displayed as ‘normal’ in the case of the measured speed of more than 50 km/h, displayed as ‘delay’ in the case of the measured speed between 50 km/h and ‘the reference speed-40 km/h’, and displayed as ‘congestion’ in the case of the measured speed of less than ‘the reference speed-40 km/h’.
However, there arises a problem in that different road conditions varying according to a signal system, a road surface state, a traffic network, and the like, which are used for determining the traveling state, are not considered due to the fixed reference speed.
Also, the user terminal may be mainly used for checking a traveling state of a road frequently used during rush hour than for checking a traveling state of an unfamiliar road.
Since paths requiring traffic information such as during rush hour are likely to be fixed by most users, there arises a need for a system for providing information of where a time required for traveling on a road frequently used is either shorter than usual or longer than usual, is predicted.